I'd recommend writing your tests in Groovy/Java and running them that way. It's not ideal, but Rhino provides a handy bridge to get at the JavaScript objects.
I've written about setting it up here: http://ryanbrooks.co.uk/posts/2014-03-27-testing-rhino-js-spock/
You could always try writing your tests in Jasmine and running them with Karma. You'd need to run Karma on Rhino, which caused us problems, but you might have more luck if you use CommonJS for Rhino.
My view is that (generally) Rhino is only used these days where JavaScript needs to be executed by Java processes, in which case you probably care about testing the Java-side output, but YMMV.